George Costanza was not known for his largess, or his patience. An episode in which the Seinfeld character angrily circles New York City streets in search of a free parking space sparked something in Ben Sann. A junior in high school at the time, Sann came up with an idea George would certainly have approved of: a website that would post the rates of parking garages all over New York.

"In New York, there is a whole culture around parking," says Sann, now 24, a 2010 graduate of Washington University in St. Louis. "There are always conversations about great early-bird parking specials and the price of monthly parking or a frenzy to move the car and circle the block for a new parking space."

Despite the preoccupation with where to park, there was no centralized database of parking rates for the city. Because he didn't have a driver's license, Sann rode around New York on his bicycle gathering data. With $50,000 in startup funds (a combination of bar mitzvah savings and a loan from his father), Sann launched NYCgarages.com in 2007. The website displayed the locations, rates and specials of garages citywide, helping drivers find the closest lot at the best price.

Two years after launch, Sann added six cities to his database--including Chicago, Los Angeles and San Francisco--and changed the company name to BestParking.com. He hired bicycle messengers to gather data and developed partnerships with parking garages to add their information to the site.

Drivers loved having access to the data, but not all garage operators were happy about having their prices made available to the public. "The industry, in the past, has benefited from a lack of transparency," says Sann, who was threatened with lawsuits and plagued with cease-and-desist letters. Undaunted, he pressed on.

Edison ParkFast was one of the first parking operators to sign a contract with Sann to list its data and offer deals through his website. "We couldn't replicate the services BestParking was offering, so we signed up and went all in," says Edison executive vice president Ben Feigenbaum.

Edison listed 40 garages in New York, New Jersey and Baltimore (representing 10,000 spaces) on BestParking and started getting calls about monthly parking almost immediately. Feigenbaum estimates that 30 percent of his leads for monthly parking come from Sann's site. "We learned very quickly that it was going to be a successful relationship," he says.

BestParking's free mobile app has topped 500,000 downloads and expanded the service to 55 cities and 80 airports across the U.S. and Canada. Revenue exceeded $500,000 in 2012, thanks in part to fees earned for redeemed coupons, monthly parking contracts, airport parking reservations and licensing agreements with Garmin and Magellan GPS systems.

"We started off by saying, ‘Give us a chance in a few facilities and let us show you what we can do,' and the more we sent parking garages cars for spots that would otherwise go unfilled, our reputation and our revenues grew," Sann says. "The accuracy of our data and our relationships with parking operators keep us growing."

Creating a MAP will take no more than an hour of your time every month and will keep the lines of communication open, ensuring relationships with investors remain strong, and ultimately helping early-stage startups succeed.